Journal of the Geological Society of India

, Volume 91, Issue 3, pp 341–347 | Cite as

Influence of Overlying Roof Strata on Rib Design in Mechanised Depillaring

  • Ashok Kumar
  • Dheeraj Kumar
  • Amit Kumar Verma
  • Arun Kumar Singh
  • Sahendra Ram
  • Rakesh Kumar
Research Articles
  • 9 Downloads

Abstract

Depillaring of the existing pillars (square or rectangular in shape) by continuous miner provides irregular shaped ribs. An assessment of strength of such a rib becomes a difficult task. Literature review finds a number of approaches for the rib design but the scope of straight forward application of these approaches is limited due to the uniqueness of geo-mining conditions of the Indian coalfields. This review also finds that a wide spectrum of moderate roof conditions is yet to be properly addressed. Field studies at some depillaring operations in Indian coalfields indicated the influence of roof strata over the stability of a rib is considerably high. A systematic study of the roof strata influence on simulated models provided interesting results. A model for rib design is conceived on the basis of the simulation results. Discussing couple of field experiences of rib stability during mechanised depillaring under two different types of roof strata of Indian coalfields, this paper presents some results of the simulation along with the conceived model of a rib design.

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Copyright information

© Geological Society of India 2018

Authors and Affiliations

  • Ashok Kumar
    • 1
  • Dheeraj Kumar
    • 2
  • Amit Kumar Verma
    • 2
  • Arun Kumar Singh
    • 1
  • Sahendra Ram
    • 1
  • Rakesh Kumar
    • 1
  1. 1.CSIR-CIMFR (Council of Scientific and Industrial Research-Central Institute of Mining and Fuel Research)DhanbadIndia
  2. 2.Indian Institute of TechnologyIndian School of MinesDhanbadIndia

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